"Look, I CAME HERE FOR AN ARGUMENT, I'm not going to just stand..."

"OH, oh I'm sorry, but this is abuse."

"Oh, I see, well, that explains it."

"Ah yes, you want room 12A, Just along the corridor."

It was rude to be rude to the people paying him to be rude because it appears to the other members of the audience who were not being paid to be rude that being rude and interrupting the talk is acceptable practice.